RPM while cruising at 80mph

Point of reference, Mini Cooper roadster S turns 2950 @ 80mph.

80/3000 RPM is with the 240/55 tire on the Rocket.
 
I thought 5th gear rpm should be lower since the day I bought it.
 
Do have to admit the carpenter work does wonders for mileage!!

I don’t doubt at all that Steel gets great mileage at 90, I get phenomenal mileage cruising at 80.